Vitamin A status and ocular lesions in some rural Nigerians with onchocerciasis

The vitamin A and ocular lesions in 98 rural Nigerians who excreted microfilariae in their skin tissues and had at least one clinical manifestation of onchocerciasis were investigated. The highest prevalence rate of 18 (69.2%) occurred among adult males with leopard skin. The overall mean vitamin status of (20.3 plus or minus 2.6 mu g/dl) was comparatively lower ( chi super(2) = 41.0; p>0.05) than the control inhabitants (76.2.3 plus or minus 3.8 mu g/dl). The mean vitamin status was higher among the infected children (22.7 plus or minus 0.5 mu g/dl) than their adult counterparts (17.9 plus or minus 6.1 mu g/dl). Also the mean vitamin A status of their infected children (22.7 plus or minus 5.0 mu g/dl) was lower ( chi super(2) = 31.1; p> 0.05) than their control subjects (73.5 plus or minus 2.1 mu g/dl). The vitamin A status of the infected adults (17.9 plus or minus 6.1 mu g/dl) was lower ( chi super(2) = 47.2; p>0.05) than their control counterparts (78.9 plus or minus 4.1 mu g/dl). The mean microfilarial load of the different age groups of the infected volunteers showed negative correlation with the mean vitamin A status (r = -0.93). In all, five different ocular lesions namely cataract, optic atrophy, chroroidoretinitis, iriodocyclitis and sclerosing keratitis were reported. Visual impairment was absent and the ocular lesions were low among the children as they had only optic atrophy and sclerosing keratitis among the five different lesions encountered.